Effects of encainide on myocardial contractility of cat papillary muscle.
The action of a new effective antiarrhythmic agent, encainide, was studied with respect to the mechanical performance of isolated cat papillary muscle. Encainide (0.1-10 micrograms/ml) did not alter the performance of cardiac muscle during either the contraction or relaxation phase. By contrast, lidocaine (1-5 micrograms/ml) caused a slight but statistically significant depression of myocardial contractility in terms of the force-velocity-length analysis, while it did not affect load clamp analysis, zero load clamp analysis and load dependence of relaxation.
D000813:Anilides / Q000494:pharmacology*; D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000494:pharmacology*; D002415:Cats; D016700:Encainide; D005260:Female; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D010210:Papillary Muscles / Q000187:drug effects* / Q000502:physiology*
D000813:Anilides; D000889:Anti-Arrhythmia Agents; D016700:Encainide